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Impact of gari consumption
on the water resource of Nigeria
O. Adeoti*, T. A. Ayelegun and B. A. Oyewole
Department
of Agricultural Engineering, Federal Polytechnic, PMB 5351,
Ado Ekiti, Ekiti State, Nigeria.
*Corresponding author. E-mail:
olusegunadeoti@yahoo.co.uk.
Tel: +234
(0) 80 34 56 24 76.
Accepted
27 November, 2009 |
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The consumption of gari (or roasted cassava granule) is
connected to a chain of impacts on the water resource in the
country where cassava crop is grown, processed and consumed.
The aim of this paper is to assess the impact of gari
consumption on the water resource of Nigeria. The paper
elaborates on two types of impact: evaporation of
infiltrated rainwater for cassava plant growth (green water
use) and the abstraction of ground and/or surface water for
processing, including that of consumption at household level
(blue water use), while water pollution impacts during
processing and consumption (at households) are neglected.
Using the 2007 cassava production estimates for Nigeria as
baseline, the water impact related to the consumption of
gari either as snack or as “eba” (gari reconstituted with
hot water to form a dough-like paste) is estimated at 10.52
x 109 m3, out of which 0.38% is due to
the use of blue water and 91.3% is due to the use of green
water (no dilution water impacts measured in this paper).
Under the traditional farming practices, the major volume of
water needed to grow the cassava plant is from rainwater.
For the total water needed in gari consumption starting from
cultivation, the water used in the processing and
consumption (at household level) is a significant fraction
(about 0.4%) of the soil moisture used to grow the cassava
plant. However, the impact of this fraction is often
significant: One, it is the blue water (abstracted from
surface and/or sub-surface sources) that is often scarcely
available and two, it is this blue water sources that are
also polluted by the waste flows from the processing and
consumption sites.
Key
words:
Water footprint, virtual water, water resource, blue water,
green water, roasted cassava granule (or, gari), Nigeria. |
